Friction clutch member



, 1936. E P E 2,035,916

FRICTION CLUTCH MEMBER auna-$222522 Z mmmmw 21 M J7Z/e7zfo71' Geoqye 1 0e.

March 31, 1935. E PQPE 2,035,916

FRICTION CLUTCH MEMBER Filed Dec; 6, 1933 3 Sheets-Sheet 2 I 50 1 10 16fiw a March 31, 1936. G. E. POPE 2,035,916

FRICTION CLUTCH MEMBE R Filed Dec. 6, 1933 3 Sheets-Sheet 3 fiz/nfor:

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Patented Mar. 31, 1936 TATES PATENT OFFICE FRICTION CLUTCH MEMBERApplication December 6, 1933, Serial No. 701,162

2 Claims.

This invention relates to improvements in clutch plate constructions andrefers specifically to the provision of a clutch plate constructionwhich permits a relatively resilient or cushioned engagement between adriving and driven member without sacrificing the efiiciency of thefriction facings or shortening the life of said facings.

The advantages and desirability of a resilient or cushioned engagementbetween the driving and driven member or members of a clutch mechanismare well recognized. Many constructions have heretofore been proposedwhich have been designed to impart resiliency or smoothness ofengagement to clutches, but in substantially all instances thecushioning effect secured has been obtained at a sacrifice of efficiencyand through subjecting the friction facings to excessive local wear.

One of the most common forms of prior art constructions which is ingeneral exemplary of all of the rest comprises the provision of one ormore clutch plates, the face or faces of which adjacent their peripheryare distorted, corrugated or portions are struck up to form cantileversprings over which the friction facings are mounted. The friction facingthus more or less conforms to the irregular base upon which it ismounted and consequently presents a series of high and low areas orundulations. These undu- 30 lations are, of course, purposely formed sothat when the clutch ring or rings are brought into contact with thefacings, said rings initially contact the high portions of the facingswhich, being supported by resilient tongues or corrugations, ofler adegree of resiliency to the engagement. However, it can readily be seenthat the clutch facings used in this manner are subjected to abnormallocal wear at said high portions and the life of the facings is therebymaterially reduced.

In my invention, resiliency is obtained in engagement of the driving anddriven members without sacrificing the life of the friction facin'gs,initial contact as well as contact throughout the entire throw of theclutch rings, of the entire area of said rings and the entire area ofsaid facings being obtained.

Briefly described, my invention comprises the provision of a pair ofparallel clutch plates adjacent their peripheries being provided withstruck up cantilever tongues which extend inwardly so as to obtaincontact between the tongues and the opposite plate. Clutch facings maybe mounted upon the outer faces of said mounted upon a hub, the faces ofsaid plates plates adjacent the plate peripheries and inasmuch as saidouter faces are flat, said facings are maintained in fiat condition.Consequently, when pressure is applied to the facings by the clutchrings the entire areas of said facings are brought into contact withsaid rings, and resiliency is obtained by flexing the cantilever tonguesagainst the inner opposite faces of the plates.

Other objects and advantages of my invention will be apparent from theaccompanying draw- 10 ings and following detail description.

In the drawings, Fig. 1 is a top plan view, parts being broken away ofan embodiment of a clutch plate comprising my invention.

Fig. 2 is a. sectional view taken on line 22 of 15 Fig. 1.

Fig. 3 is a sectional view taken on line 8-3 Fig. 1.

Fig. 4 is a fragmentary sectional view of a modified form of hubattachment.

Fig. 5 is a fragmentary sectional view, showing the cantilever tonguesinitially compressed.

Fig. 6 is a view similar to Fig. 1 illustrating a. modified form ofmeans for limiting movement of the plates. 25

Fig. 7 is a sectional view taken on line 1-1 of Fig. 6.

Fig. 8 is a detail plan view of one of the plate movement limiting lugs.

Figs. 9, 10, 11 and 12 are fragmentary top plan 30 views illustratingmodified shapes of cantilever tongues.

Fig. 13 is a view similar to Fig. 1, illustrating my invention used witha clutch plate having torsion springs.

Fig. 14 is a. sectional view taken on line "-14 of Fig. 13.

Fig. 15 is a graph showing various pressuredefiectlon curves.

Referring in detail to the drawings, 1 indi- 4 cates a clutch plateconstructed according to the concepts of my invention. The plate Icomprises hub 2, the internal portion of which may be provided withsplines 3 which are adapted to engage the splines of a clutch shaft (notshown) 45 whereby said clutch plate is slidable but nonrotatable uponsaid clutch shaft. An annular flange 4 may extend from the outer surfaceof the hub 2 and may be formed integral with said hub, said flange beingprovided with radially 50 spaced openings for the reception of rivets 5.Each of the rivets 5 may be of restricted diameter throughout asubstantial portion of its length, as indicated at 6 and 1 in Fig. 2, anintermediate portion of said rivet being enlarged as shown at 8.

be confined between the annular flange 4 and the enlarged portions 8 ofeach of the rivets. In this manner disk 9 is rigidly mounted upon hub 2.Disk I0 may be provided with a plurality of apertures suitable in sizeto fit over the enlarged portions 8 of rivets 5. An annular ring II maybe provided with a plurality of radially spaced apertures adapted toreceive the restricted portions 1 of each of the rivets. It can readilybe seen that ring I I, which is confined between the enlarged portions 8and the heads I2 of the rivets 5, will be maintained rigid with respectto hub 2. The arrangement is such, however, that disk l9 may havelimited movement with respect to disk 9, the outer movement beingrestricted by ring II. The purpose of this construction will behereinafter more fully described.

A plurality of tongues I3 may be struck up from the surfaces of thedisks 9 and Ill adjacent their outer peripheries, said tongues beingspaced on opposite disks in staggered relationship. The tongues I3struck up from disk 9 may extend inwardly'toward disk It and, thetongues I3 struck up from disk In may extend inwardly toward disk 9 sothat a portion of the tongues from one disk contacts a portion of theplane surface of the opposite disk. In this manner the disks 9 and IIIare maintained in spaced relationship with respect to each other.

An annular friction facing It may be mounted upon the outer face of disk9 and in like manner a friction facing I5 may be mounted upon acorresponding portion of disk III, the facings It and I5 beingconstructed of a material having desirable frictional characteristics.As shown best in Figs. 1 and 2, the friction facing I5 may bemaintainedupon the face of disk I9 by means of rivets I6, said rivets beingdisposed in staggered relationship upon an inner and outer radius, asshown best in Fig. 1. The head I? of each of the rivets I6 may bepositioned on the inner face of disk I0 and the expanded portion I8 ofsaid rivets may be positioned in recesses provided in the face of thefriction material I5. An aperture I9 may be provided in disk 9 at apoint opposite each of the rivet heads Ii. In addition, an aperture 29may be provided in the facing Id adjacent each aperture I9. The frictionfacing I i may be mounted upon disk 9 by means of rivets M, the heads 22of said rivets being positioned adjacent the outer face of disk III,facing i5 being provided with apertures 23 adjacent each of said rivets.The expanded portion 29 of rivets 2i may be positioned in recessesprovided in the face of friction material Id. The arrangement is suchthat friction facing It is rigidly mounted "upon disk 9, the samebeing'confined between the expanded portion 29 of the rivets 2i andshoulders 25 of said rivets. However, head 22 of each of the rivets 2Imerely limits outward movement of disk In with respect to disk 9, diskIt being-movable toward disk 9.

It can readily be seen that by means of the struck-up tongues I3, disks9 and I0 are maintained in spaced relationship, the outward movement ofdisk It with respect to disk 9 being limited by the heads 22 of rivets2| and by ring II. Consequently, disks 9 and III and, hence, frictionfacings I I and I5, are normally maintained in fixed parallelrelationship with respect to each other.

In operation, plate I may be slidably mounted upon the clutch shaft, thefacings I4 and I5 being respectively positioned adjacent a drivingmember and a pressure actuated clutch ring (not shown). The drivingmember, of course is to be connected to the clutch shaft through themedium of the clutch plate. In the usual automobile clutch mechanism,the clutch ring is normally in contact with one of the friction facingsimpelling the clutch plate and the opposite friction facing into contactwith another clutch ring or into contact with the fiywheel of theinternal combustion engine. When the clutch pedal is depressed, thepressure upon the clutch plate is relieved and consequently noconnection exists between the internal combustion engine and the clutchshaft.

It can readily be seen that in using the clutch plate I when pressure ofthe clutch ring is ex erted upon one of the friction facings tending tobring the opposite facing into contact with the driving member, thecantilever tongues I3 are flexed between theadjacent disks 9 and III. Inthis manner a degree of resiliency is imparted to the clutch connection.

As a feature of my construction, the facings It and I5 are appliedto theouter surfaces of the respective disks 9 and Ill, said surfaces beingrelatively fiat. Inasmuch as the cantilever tongues I3 are struck upinwardly from the facing, no high spots are produced upon the frictionsurfaces of the facings and, consequently, said surfaces are maintainedin a fiat condition. It can readily be seen, therefore, that the entirearea of each of the facings I9 and I5 is brought into contact withrespectively, the driving member and the clutch ring. This is true evenat the initial contact of the clutch ring with the clutch facing. Inthis manner a smooth cushioned engagement is secured and since theentire area of the clutch facings are utilized, the life of said facingsis accordingly not sacrificed. By means of the rivets 2I and the rivets5, disk I0, when pressure is applied to the facings I6 and I5, is

free to move in such a manner as to maintain the surfaces of saidfacings in parallelism. This, of course, further tends to obtainengagement of the entire area of the facings with the entire area of thedriving member and the pressure m ember.

Referring particularly to Fig. 4, a slightly modified form of attachmentof disks 9 and ID to hub 2 is shown. Flange 9 carried by hub 2 may beprovided with a plurality of radially spaced apertures for the receptionof rivets 26 which are of uniform diameter thoughout their length. Disks9 and I0 may be mounted upon hub 2 and may be confined between theannular flange 9 and ring II, said disks being spaced from each other bymeans of an annular spacer 2'! which may be provided with radiallyspaced apertures through which rivets 25 are adapted to pass. Theremaining construction of the clutch plate may be similar to thestructure of plate I. In this construction, when pressure is applied tofacings MI and I5, disks 9 and I9 being fixed at the hub 2, will beslightly flexed. However, said disks possess suflicient inherentresiliency to permit said facings to be maintained substantially par-.allel when pressure is applied. This is particu- Cal larly true when itis considered that the spacing between disks 9 and I0 is relativelyslight as compared with the radius of said disks. In many instances thisform of mounting may be preferred.

Referring particularly to Figs. 6, 7 and 8, a slightly modified means oflimiting the spacing of the disks is shown. In this modification the hubconstruction and the means for mounting the disks upon said hub may besimilar to that shown in Figs. 2 and 4. The disks may be provided withstruck-up cantilever tongues I3 similar to the tongues described inconjunction with plate I. The only difference in the constructionresides in the substitution of members 28 for rivets 2 I, said membersperforming the same function as said rivets, in other words, saidmembers are adapted to limit the movement of disks 9 and I0 away fromeach other. In the embodiment shown in Figs. 6, 7 and 8, a series oftongues 29 may be struck up from disk I0 which may correspond to diskI0. Disk 9' which corresponds to disk 9 may be provided with apertures30 opposite the struck-up tongues 29 and in addition, facing It may alsobe provided with apertures 3I adjacent apertures 30. In this form of myinven-. tion each clutch facing It and I 5 is secured upon the disks 9'and I0 by means of rivets I6 in a manner identical to the securing offacing I5 upon disk I0 in plate I.

In assembling the form of my invention shown in Figs 6, 7 and 8, tongues29 struck up from disk may be inserted in apertures 30 provided in disk9'. Disk I0 may then be slightly rotated with respect to disk 9' so asto cause tongues 29 to overlap those portions of disk 9' adjacentapertures 30, bringing the disks 9' and I0 into the position shown inFig. 7. When this relative position is obtained the rivet apertures inthe disks d and I0 adjacent hub 2 will be found to' be in coincidenceand said rivets may be adapted to secure disks 9 and I0 upon said hub inthe manner described in conjunction with plate I. It can readily beseen' that in this form of my invention disks 9' and Id, being spacedfrom each other by means of the cantilever tongues I3, are free to movetoward each other when said tongues are flexed. However, when thepressure upon the facings is released and disks 9 and i0 tend toseparate from each other, the movement of the disks away from each otheris limited by tongues 29. 4

- Referring particularly to Figs. 13 and 14, another modifled form of myinvention is shown as utilized in conjunction with a clutch plate 32having torsional resiliency. The plate 32 may comprise hub 33 havingsplines 3@ upon its internal portion and an annular outwardly extendingflange 35. Flange 35 may be provided with a plurality of radially spacedapertures for the reception of rivets 38 which may be adapted to securespaced annular rings 37 and 238 to hub 33. Rings 3'8 and 38 may beprovided with radially spaced apertures adjacent their-outer peripheriesfor the reception of rivets 30. A pair of disks t0 and 4! may be carriedbetween the spaced rings 31 and 38, said disks being providedintermediate their width with relatively enlarged apertures 62 whichcorrespond in number and spacing to rivets t9. Rivets 39 may berelatively enlarged intermediate their lengths, as shown best at 63 inFig. 14, whereby plates 31 and 38 are maintained in spaced relationship.The diameter of the enlarged portion 63 of the rivets 39, however, isless than the diameter of the apertures 42.

40 and 4| and rings 31 and 38 defining apertures 44 and 41 respectively.

The faces of disks 40 and ll adjacent the outer peripheries thereof maybe provided with struckup tongues 49, similar to tongues I 3 and thefunction of said tongues is identical with the function of tongues I 3.Friction facings I4 and I5 identical with the facings utilized in plateI may be mounted in an identical manner as the facings on plate I, andthe outer movement of said disks may be restrained in the same manner aswith the disks 9 and I0.

The operation of plate 32 in a clutch mechanism is substantially similarto the operation of plate I. Facings I4 and I5 are maintained inparallelism during engagement and all of the advantages of plate I arealso inherent in plate 32. In addition, the construction is such thattorsional resiliency is also obtained. It can readily be seen thatwhenpressure is applied to facings I4 and I5 and motion of rotation isimparted to the clutch plate 32, a slight rotational movement of disks410 and AI takes place independent of hub 33. When the rotational forceis first applied, disks {0 and di are shifted against the compression ofsprings 08, the opposite ends of said springs abutting rings 31 and 38.This relative movement, of course, is permitted'by the oversizeapertures d2 surrounding rivets 39. Consequently, clutch plate 32 inaddition to possessing a degree of axil resiliency due to springs ea,also s a degree of torsional resiliency. Hence, the engagement of aclutch having a clutch plate or clutch plates of this construction isextremely cushioned and velvety.

Referring particularly to Fig. 15, a graph is shown, drawn with poundspressure as abscissae, that is, the spring pressure of the clutch ringagainst the friction facing and percentage defiection or collapse of thefriction member as ordinates. In the usual automobile clutch mechanismthe spring pressure is substantially proportionate to movement of theclutch pedal. A curve plotted between these coordinates determines theengaging characteristics of the clutch mechanism in regard to smoothnessof engagement, for instance, curve A illustrates the characteristics ofa clutch the friction member of which is deflected or collapsed more orless rapidly. As can be observed from the curve, deflection is reachedearly in the travel of the clutch pedal considering that 1600 pounds isthe maximum spring pressure exerted. Curve B in dicates. a clutchmechanism having more desirable engaging characteristics, the engagementbeing more or less gradual, complete collapse or deflection not beingobtained until the clutch pedal has travelled substantially of its totaldistance. Curve C indicates the engagement characteristics of a clutchmechanism which is even superior to that indicated by curve B. It can beseen from curve C that engagement is relatively gradual and thatcomplete deflection or collapse of the friction member does not occuruntil almost maximum spring pressure has been exeited. Both curves B andC are exemplary of the characteristics of clutch plates similar to plateI or plate 32, whereas curve A is exemplary of the characteristics of aclutch having the conventional type clutch plate.

Referring particularly to Figs. 9, 10, 11 and 12,

clutch disks having different shaped cantilever tongues are shown. Inthe form shown in Fig. 9, the clutch disk is provided adjacent its outerperiphery with trapezoidal struck-up tongues 5|, said tongues beingstruck up in a manner similar to tongues l3 and 49 in plates l and 32.Friction facings 52 may be mounted upon the face of each of the disks 50in a manner similar to the mounting of facings l4 and I5 hereinbeforedescribed.

In Fig. 10, clutch disk 53 may be provided with tongues 54 which may berounded at their corners. Clutch disk 55 may be provided with tongues56, each of which may comprise a plurality of separate cantilever strips51, 58 and 59, the strips being of different length. In Fig. 12, disk 60may be provided with tongues 6|, the tongues being cut at their ends ina stepwise manner as shown best at 52 in Fig. 12.

As can be readily seen, inasmuch as the clutch disks are maintained inspaced relationship by means of the struck-up tongues, and as is Wellknown, the deflection of the usual cantilever beam is dependent upon itslength, area and cross sectional dimensions, means is provided forcontrolling the deflection or collapse of a friction member. In otherwords, by changing the shape of the tongues as indicated in Figs. 9, 10,11 and 12, or by cutting said tongues in any other desired shape, theshape or contour of the pressure-deflection curve may be altered.Consequently, by the use of my invention, the engaging characteristicsof a friction member may be so controlled as to obtain the desireddegree of smoothness under any conditions.

I claim as my invention:

1. A clutch plate comprising in combination, a hub, an annular flangeextending radially outwardly from said hub, a metal disk, rivets rigidlysecuring said metal disk to said hub, a second metal disk, positionedupon said rivets parallel to said first mentioned disk, said second diskbeing movable in planes parallel to said first mentioned disk, anannular ringrigidly mounted upon said rivets serving to limit outwardmotion of said movable disk with respect to said first mentioned disk, afriction facing mounted upon the outer face of each disk, the frictionsurfaces of said facings being fiat and substantially parallel to eachother and to said disks, a plurality of resilient tongues struck upinwardly from each disk from beneath the friction facing upon said disktoward said opposite disk to maintain said disks resiliently impelledaway from each other.

2. A clutch plate comprising in combination, a hub, an annular flangeextending radially outwardly from said hub, a metal disk, rivets rigidlysecuring said metal disk to said hub, said rivets having intermediateportions of enlarged diameter, a second metal disk positioned upon saidenlarged portions of said rivets, said second disk being movable inplanes parallel to said first mentioned disk, an annular ring rigidlymounted upon said rivets and clamped between said enlarged portionsthereof and the heads of the rivets 5 serving to limit outward motion ofsaid movable disk with respect to said first mentioned disk, a frictionfacing mounted upon the outer face of each disk, the friction surfacesof said facings being fiat and substantially parallel to each other andto said disks, a plurality of resilient tongues struck up inwardly fromeach disk from beneath the friction facing upon said disk toward saidopposite disk to maintain said disks resiliently impelled away from eachother.

' GEORGE E. POPE.

